Hydrophytes of the oases in the Sierra de la Giganta of Central Baja California Sur, Mexico: Floristic composition and conservation status   总被引：1，自引：0，他引：1  

J.L. Len de la Luz  R. Domínguez Cadena 《Journal of Arid Environments》2006,67(4):553-565

One of the features of the Sierra de la Giganta mountain range is the existence of many small riparian wetlands (oases) along drainage channels. There are no geohydrological studies from which to determine their dynamics in the arid environment, but these areas confront increasing water extraction to satisfy demands of small local settlements. This study compiled a checklist of the hydrophytes from 12 representative oases, and discusses their current status on the basis of composition, richness, and species characteristics. Floristic composition (absence–presence of 57 hydrophytes) at each location was classified by using UPGMA to represent a dendrogram of group cohesivity. Two major kinds of locations are present. By analysing individual site characteristics, we found that one group occurs in places under “good conservation conditions” and the other composed of locations that are “impacted” in several ways. The former group contains oases that are relatively rich in species, including most of the aquatic forms, which are sensitive to disturbance. Geographical affinity of the floristic list reveals that most species have a broad distribution, mostly in tropical America.  相似文献   

基于ArcEngine的乌梁素海湿地数据库管理系统设计   总被引：1，自引：1，他引：0  

韦玮  崔丽娟  李胜男  郭嘉  郑平 《湿地科学与管理》2011,7(4):31-34

针对乌梁素海湿地数据管理的需求,采用ArcGIS Engine工具包进行乌梁素海湿地资源数据库管理系统的设计。从乌梁素海湿地数据管理的需求分析、数据的采集与集成,到湿地数据库系统的设计及该系统需要实现的功能等方面,详细阐述了数据库管理系统的结构和功能;并对该数据库系统功能的数据管理模块、图形制作模块和湿地数据分析模块等进行了介绍和描述。该数据库系统既是乌梁素海湿地生态系统健康诊断的数据基础,又是乌梁素海湿地资源信息综合智能管理平台的基础数据来源,对乌梁素海湿地资源数据的管理及湿地恢复与重建辅助决策支持的应用有着重要的意义。  相似文献   

黄河三角洲湿地生态特征变化及可持续性管理对策   总被引：54，自引：10，他引：54  

崔保山  刘兴土 《地理科学》2001,21(3):250-256

近年来，由于农业市场化和产业化的发展，工业与城市化的崛起，黄河三角洲湿地生态特征发生了巨大变化。表现在湿地类型和面积的改变，湿地水状况及水质的变化，湿地产品的不可持续利用等，通过对湿地生态变化的自然因素和人为原因进行分析，提出了黄河三角洲湿地可持续性管理的方案，并从生态、社会、经济指标出发，探讨了湿地可持续性管理对策。  相似文献   

湿地生态过程研究进展   总被引：62，自引：2，他引：62  

何池全  赵魁义  余国营  赵志春  王国平 《地球科学进展》2000,15(2):165-171

湿地生态过程的研究是湿地研究的核心内容,是研究其物理过程、化学过程和生物过程及其相互关系以及这些过程与湿地功能的关系。介绍湿地生态过程的概念,并对湿地生态过程的三个方面即有机物的生产过程(生物过程)、营养物质循环(化学过程)和能量流动及其水文过程(物理过程)的研究进展进行了述评,并对生物过程、化学过程和物理过程的研究方法进行了剖析,同时对生态过程的研究前景进行了简要分析。  相似文献   

Improved coastal wetland mapping using very-high 2-meter spatial resolution imagery     

《International Journal of Applied Earth Observation and Geoinformation》2015

Accurate wetland maps are a fundamental requirement for land use management and for wetland restoration planning. Several wetland map products are available today; most of them based on remote sensing images, but their different data sources and mapping methods lead to substantially different estimations of wetland location and extent. We used two very high-resolution (2 m) WorldView-2 satellite images and one (30 m) Landsat 8 Operational Land Imager (OLI) image to assess wetland coverage in two coastal areas of Tampa Bay (Florida): Fort De Soto State Park and Weedon Island Preserve. An initial unsupervised classification derived from WorldView-2 was more accurate at identifying wetlands based on ground truth data collected in the field than the classification derived from Landsat 8 OLI (82% vs. 46% accuracy). The WorldView-2 data was then used to define the parameters of a simple and efficient decision tree with four nodes for a more exacting classification. The criteria for the decision tree were derived by extracting radiance spectra at 1500 separate pixels from the WorldView-2 data within field-validated regions. Results for both study areas showed high accuracy in both wetland (82% at Fort De Soto State Park, and 94% at Weedon Island Preserve) and non-wetland vegetation classes (90% and 83%, respectively). Historical, published land-use maps overestimate wetland surface cover by factors of 2–10 in the study areas. The proposed methods improve speed and efficiency of wetland map production, allow semi-annual monitoring through repeat satellite passes, and improve the accuracy and precision with which wetlands are identified.  相似文献   

污水处理型人工湿地构建中几个问题的探讨     

杨琇楦  施瑶  王忠强  何春光  程明明 《湿地科学与管理》2015,11(2):8-11

污水处理型人工湿地是利用基质、湿生植物协同净化水体污染物,具有良好的景观价值与生态功能。目前,人工湿地的实际构建中,在基质和植物选择、运行管理中存在一系列问题,就这几方面问题进行分析并探讨解决方案和思路。  相似文献   

Reactive transport in stratified flow fields with idealized heterogeneity     

James N. Carleton  Hubert J. Montas 《Advances in water resources》2009

A two-dimensional equation governing the steady state spatial concentration distribution of a reactive constituent within a heterogeneous advective–dispersive flow field is solved analytically. The solution which is developed for the case of a single point source can be generalized to represent analogous situations with any number of separate point sources. A limiting case of special interest has a line source of constant concentration spanning the domain’s upstream boundary. The work has relevance for improving understanding of reactive transport within various kinds of advection-dominated natural or engineered environments including rivers and streams, and bioreactors such as treatment wetlands. Simulations are used to examine quantitatively the impact that transverse dispersion (deviations from purely stochastic-convective flow) can have on mean concentration decline in the direction of flow. Results support the contention that transverse mixing serves to enhance the overall rate of reaction in such systems.  相似文献   

Quantitative assessment on basin-scale hydrological services of wetlands     

Wu  Yanfeng  Zhang  Guangxin  Rousseau  Alain N. 《中国科学:地球科学(英文版)》2020,63(2):279-291

Despite recognizing the importance of hydrological function of wetlands, basin-scale wetlands services have rarely been investigated. The PHYSITEL/HYDROTEL modelling platform was used to quantitatively assess the impact of wetlands on quickflow and baseflow with paired simulation scenarios in Duobukuli River Basin, namely with wetlands and without wetlands.Simulation results showed that wetlands exert significant impact on basin hydrological processes by decreasing streamflow and altering streamflow regime(magnitude, frequency, duration and time of flow events). The intensity(significant or not) of wetlands influences on quickflow had daily, monthly and annual variation. Wetlands significantly attenuated quickflow during flood season while slightly support daily, monthly and annual baseflow. The average quickflow attenuation and baseflow support of wetlands were 5.89% and 0.83%, respectively. Although the intensity and effect(mitigation or augment) of wetlands on streamflow temporally varied at daily, monthly, seasonal and annual scales, wetland overall mitigated quickflow and augment baseflow in Duobukuli River Basin. Our results could provide insights for future decision-making for rehabilitation and conservation of wetlands as well as integrated basin water resources management.  相似文献   

山东省渤海沿岸湿地价值估算与保护对策     

王岳林  张太平  韩树红 《山东地质》2011,(3):30-34

山东省渤海沿岸湿地价值估算的目的是提醒公众尤其是政府决策部门关注湿地的综合功能,而不是也不应该单纯向湿地索取,更不能破坏性地开发,需要科学保护和合理利用,以使湿地可持续利用。通过分析湿地动态影响因素,提出了湿地保护管理的对策措施。  相似文献   

山东省渤海沿岸湿地价值估算与保护对策     

王岳林  张太平  韩树红 《山东国土资源》2011,27(3):30-34

山东省渤海沿岸湿地价值估算的目的是提醒公众尤其是政府决策部门关注湿地的综合功能,而不是也不应该单纯向湿地索取,更不能破坏性地开发,需要科学保护和合理利用,以使湿地可持续利用。通过分析湿地动态影响因素,提出了湿地保护管理的对策措施。  相似文献